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RAN Capacity Monitoring Guide (BSC6910-Based)Contents

5.4.4 RAN Capacity Monitoring Guide (BSC6910-Based)

RAN16.0Capacity Monitoring Guide (BSC6910-based)

Issue 01

Dat e 2014-04-29

Page 1 of 42RAN Capacity Monitoring Guide (BSC6910-Based)

8/5/2014http://localhost:7890/printtopics.html?time=Tue Aug 5 17:47:22 UTC+0700 2014


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HUAWEI TECHNOLOGIES CO., LTD.




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Copyright © Huawei Technologies Co., Ltd. 2014. All rights reserved. No part of this document may be reproduced or transmitted in any form or by any means without prior written consent of Huawei Technologies Co., Ltd.

Trademarks and Permissions

and other Huawei trademarks are trademarks of Huawei Technologies Co., Ltd.All other trademarks and trade names mentioned in this document are the property of their respectiveholders.

NoticeThe purchased products, services and features are stipulated by the contract made between Huawei and thecustomer. All or part of the products, services and features described in this document may not be within the

purchase scope or the usage scope. Unless otherwise specified in the contract, all statements, information,and recommendations in this document are provided "AS IS" without warranties, guarantees or representations of any kind, either express or implied.The information in this document is subject to change without notice. Every effort has been made in the

preparation of this document to ensure accuracy of the contents, but all statements, information, andrecommendations in this document do not constitute a warranty of any kind, express or implied.

Huawei Technologies Co., Ltd.

Address: Huawei Industrial Base

Bantian, LonggangShenzhen 518129People's Republic of China

Website: http://www.huawei.com

Email: [email protected]




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About This Document

1.1 Purpose

Growing traffic in mobile networks, especially in newly deployed networks, requires more and more network resources,such as radio and transmission resources. Lack of network resources will affect user experience. Therefore, monitoringnetwork resources, locating bottlenecks, and performing capacity expansion in real time are critical to the provision of highquality services.

This document describes how to monitor the usage of various network resources and locate network resource bottlenecks.

This document applies to BSC6910s and 3900 series base stations.

Radio Network Controllers (RNCs) mentioned in this document refer to Huawei BSC6910s.

For details about the MML commands, parameters, alarms, and performance counters, see section "Operation andMaintenance" in BSC6910 UMTS Product Documentation or 3900 Series WCDMA NodeB Product Documentation.

For details about flow control, see Flow Control Feature Parameter Description in the RAN Feature Documentation.

1.2 Organization

This document is organized as follows:

Change HistoryThe latest document issue contains all changes made in previous issues.

01 (2014-04-21)

This issue includes the following changes:

Draft A (2014-01-27)

Compared with the 06 (2014-01-20) of RAN15.0, issue draft A of RAN16.0 includes the following changes:

Chapter Description1 Overview Introduces network resources and monitoring methods.2 Network ResourceMonitoring

Provides capacity monitoring principles, monitoringmethods, and optimization suggestions.

3 Network ResourceTroubleshooting

Provides methods for analyzing and locating networkcongestion and overload problems.

4 Metrics Definitions Provides a table that includes all metrics currently in use.5 Reference Documents Lists the documents referenced within the text and

provides the document name, document package, anddocument package download path athttp://support.huawei.com.

Change Type Change DescriptionFunction change None.Editorial change The figures are optimized.

Change Type Change DescriptionFunction change Add new monitoring counters in sections 2.5.2.Editorial change None.




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Contents

About This Document

1.1 Purpose

1.2 Organization

1 Overview

1.1 Network Resources1.2 Monitoring Methods

2 Network Resource Monitoring

2.1 Monitoring Metrics and Procedure

2.2 CP/UP CPU Load

2.3 RMP CPU Load

2.4 Interface Board CPU Load

2.5 SCU CPU Load

2.6 Common Channel Usage

2.7 Downlink Load

2.8 Uplink Load

2.9 OVSF Code Usage

2.10 CE Usage

2.11 Iub Bandwidth Usage

2.12 NodeB CNBAP Load

2.13 HSPA Users

3 Network Resource Troubleshooting

3.1 Possible Block and Failure Points in the Basic Call Flow

3.2 Counters Related to Call Congestion

3.3 Resource Usage Analysis

4 Metrics Definitions

5 Reference Documents




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1 Overview1.1 Network Resources

Figure 1-1 lists the network resources to be monitored.

Figure 1-1 Network resources to be monitored

1.1.2 RNC Resources

The RNC resources to be monitored include the following:

Control Plane/User Plane (CP/UP)

In the RNC, EGPUa boards process signaling on the CP and services on the UP. With an increase in the traffic volume, ifthe CP and UP loads of EGPUa boards exceed the predefined processing capacity, CP/UP will become a system bottleneck.

Resource Management Processing (RMP)

RMP is the main processing unit.

Interface Board (INT)

RNC interface boards provide transmission ports and resources, process transport network messages, and exchange data between RNC boards and between the RNC and external devices. Resource overload on interface boards increases the packet loss rate, interrupts communications, and affects user experience.

GE Switching network and Control Unit (SCU)

SCU provides the function of inter-subrack information exchange in the RNC. When the traffic volume of inter-subrackcommunication approaches the overload threshold, voice service quality, data service quality, and network KPIs deteriorate,causing the system to become unstable.

1.1.3 NodeB Resources

The NodeB resources to be monitored include the following:

Channel Element (CE)

CEs are baseband processing resources. Generally, CEs are most likely to be congested on a network. In the early phase ofnetwork deployment, traffic volume is often small. Operators only need to purchase a small number of CEs, which reducestheir capital expenditure (CAPEX).

Iub interface bandwidth

The Iub interface exists between the NodeB and RNC. The interface uses asynchronous transfer mode (ATM) or IPtransmission depending on the transmission medium. Insufficient Iub interface bandwidth leads to admission failures,transmission KPI deterioration (such as delay, jitter, and packet loss rate), and UMTS service quality degradation.

Common NodeB Application Part (CNBAP)

CNBAP load is used to assess the NodeB processing capacity. CNBAP overload lowers the NodeB processing capacity,which then affects KPIs related to the NodeB.

HSPA users




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HSPA services are mainly carried on the WBBP boards in a NodeB. Therefore, the number of HSPA users determinesWBBP board loads. If WBBP boards are overloaded with HSPA users, new users may fail to access the network.

1.1.4 Cell Resources

The cell resources to be monitored include the following:

Received Total Wideband Power (RTWP)

RTWP includes receiver noise, external radio interference, and uplink power. RTWP is used to monitor uplink load.Transmitted Carrier Power (TCP)

TCP refers to the full-carrier power transmitted by a cell. It is used to monitor downlink load. The TCP value is limited bythe maximum transmit power of the power amplifier in a NodeB and the maximum transmit power configured for a cell.

Orthogonal Variable Spreading Factor (OVSF)

Insufficient downlink OVSFs affect UEs' access to the network.

Paging Channel (PCH)

PCH usage is affected by the location area and routing area planning. PCH overload decreases the paging success rate.

Random Access Channel (RACH) and Forward Access Channel (FACH)

RACH and FACH carry signaling and a small amount of user-plane data. RACH or FACH overload decreases the networkaccess success rate and affects user experience.

1.2 Monitoring Methods

Network resources can be monitored using the following two methods:

Proactive monitoring: This is a method for monitoring various network resources simultaneously. When resourceconsumption is consistently greater than its upper threshold, perform capacity expansion to relieve resource congestion. Thismethod is easy to implement and suitable for daily resource monitoring. For details, see chapter 2 "Network ResourceMonitoring."

Problem-driven analysis: This analysis finds system bottlenecks by locating problems. As an example, capacity analysis istriggered by issues such as call blocks. This method requires enhanced troubleshooting skills but makes full use of networkresources and eliminates the need for an immediate network expansion. For details, see chapter 3 "Network ResourceTroubleshooting."




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2 Network Resource Monitoring2.1 Monitoring Metrics and Procedure

2.1.1 Monitoring Metrics

Metrics are defined to monitor the usage or load of UTRAN resources. Resource thresholds are also recommended based onspecific criteria.

Defining peak hours is important for monitoring metrics. There are different ways to define peak hours, but you are advisedto simply use the hours during which the corresponding resource usage is the highest as peak hours.

Table 2-1 lists RNC resources, counters, and monitoring thresholds.

Table 2-1 RNC resources , counters, and monitoring thresholds

Table 2-2 lists NodeB resources, counters, and monitoring thresholds.

Table 2-2 NodeB resources, counters, and monitoring thresholds

For details about other resources, counters, and monitoring thresholds, see the corresponding sections.

2.1.2 Monitoring ProcedureThis section discusses the network resource monitoring procedure. It can be easily implemented and works in mostscenarios.

The procedure starts with individual resource monitoring. When a resource exceeds a predefined threshold, it should becross checked against other resources.

For example, if CE usage is higher than 70% but RTWP, TCP, or OVSF resources are normal, this indicates that the cellload is normal, but CEs are insufficient. In this scenario, increase the number of CE licenses or add baseband processing

boards rather than expand the NodeB capacity.

Figure 2-1 shows the resource monitoring flowchart.

RNC Resource Counter

CP CPU load VS.SUBSYS.CPULOAD.MEANUP CPU load VS.SUBSYS.CPULOAD.MEANRMP CPU load VS.CPU.CPULOAD.MEANSCU CPU load VS.CPU.CPULOAD.MEANInterface board CPU load VS.CPU.CPULOAD.MEANInterface board forwarding load VS.INT.TRANSLOAD.RATIO.MEAN

NodeB Resource Counter MoThr

CE usage VS.NodeB.ULCreditUsed.MeanVS.LC.ULCreditUsed.MeanVS.LC.DLCreditUsed.MeanVS.HW.DLCreditAvailableVS.HW.ULCreditAvailable

70%

NodeB CNBAP load VS.RadioLink.Recv.MeanVS.DedicMeaRpt.MEANVS.BTS.CnbapCap.UseRate

60%

HSPA users VS.BOARD.UsedHsdpaUserRatio.MeanVS.BOARD.UsedHsupaUserRatio.Mean

60%




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Figure 2-1 Resource monitoring flowchart

This procedure applies to most resource monitoring scenarios, but sometimes the system may be overloaded because ofother abnormalities instead of traffic increases. Some of these abnormalities can be discovered by resource cross-checking.If more extensive resource cross-checking is unsuccessful, more advanced troubleshooting is required. Chapter 3 "NetworkResource Troubleshooting" addresses the more advanced troubleshooting procedures.

For the sake of simplicity, it is assumed that there are no other abnormalities on the network during the proactive monitoring process described in chapter 2 "Network Resource Monitoring."

2.2 CP/UP CPU Load

2.2.1 Monitoring Principles




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CP is used to process Uu interface signaling and transmit control-plane signaling. CP is easily overloaded on networks thatare vulnerable to signaling storms. If CP is overloaded, new messages are discarded. That is, new call requests are rejected,which significantly affects user experience.

UP is used to process and distribute user-plane data flows. If UP is overloaded, user-plane data is partially discarded. Thiscauses voice and data service quality to deteriorate.

EGPUa boards process services on the RNC user plane and control plane. The CPs and UPs of all EGPUa boards in theRNC form a CP pool and a UP pool, respectively. The RNC can adjust the multi-core digital signal processors (DSPs)

allocated to the CPs and UPs based on service requirements in order to balance the load between the CPs and UPs.Run the ADD BRD command to set the logical function type of an EGPUa board. If the Logical function type parameter isset to UCUP, the EGPUa board is used for "UMTS RNC control-plane and user-plane processing." The following is anexample:

ADD BRD: SRN=0, BRDCLASS=GPU, BRDTYPE=EGPUa, LGCAPPTYPE=UCUP, SN=10;

Slots 8 and 9 of subrack 0 in the RNC permanently hold EGPUa boards whose logical function type is RMP, which are usedonly for resource management. Other slots can hold EGPUa boards whose logical function type is UCUP, which are usedfor UMTS RNC control-plane and user-plane processing.

If the subsystem number is "2xxx", this subsystem processes CP services. If the subsystem number is "8xxx", this subsystem processes UP services. CP CPU load and UP CPU load are monitored in CP and UP pools, respectively, without consideringthe board in which the subsystem is located.

CP and UP subsystems can be flexibly deployed using the SET UCPUPFLEXCFG command. In this command, theFlexCfgMode parameter specifies the mode for adjusting the CP and UP subsystems, and the CPProportionInTotal

parameter specifies the percentage of CPU usage for the CP in the total CPU usage. You can use these two parameters tomanually configure the ratio of CPs to UPs in order to distinguish CP and UP subsystems.

2.2.2 Monitoring Methods

The VS.SUBSYS.CPULOAD.MEAN counter provides the mean CPU usage of a subsystem in the measurement period. Itindicates the load and operating performance of the CPU on the subsystem in the measurement period.

The CP CPU load is calculated using the following formula:

CP CPU load = AVG(VS.SUBSYS.CPULOAD.MEAN)

The UP CPU load is calculated using the following formula:

UP CPU load = AVG(VS.SUBSYS.CPULOAD.MEAN)

2.2.3 Optimization Suggestions

If the CP CPU load is greater than 50% during peak hours for three consecutive days in a week, prepare for capacityexpansion. If the CP CPU load is greater than 60% during peak hours for three consecutive days in a week, perform capacityexpansion immediately.

If the UP CPU load is greater than 60% during peak hours for three consecutive days in a week, prepare for capacityexpansion. If the UP CPU load is greater than 70% during peak hours for three consecutive days in a week, perform capacityexpansion immediately.

Perform capacity expansion as follows:

When the FlexCfgMode parameter is set to ManulMode or FrozenMode , adjust the ratio of CPs to UPs or change theFlexCfgMode parameter to AutoMode if the CP pool or UP pool is overloaded.

If the current CP/UP resources cannot meet the requirements of the traffic model, add EGPUa boards.

2.3 RMP CPU Load


RMP is the main processing unit of an EGPUa board. It allocates RNC resources to each call, including CP, UP, andinterface board resources. Slots 8 and 9 of subrack 0 in the RNC permanently hold EGPUa boards whose logical functiontype is RMP, which are used only for resource management. The EGPUa boards in slots 8 and 9 work in active/standbymode.





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Use the VS.CPU.CPULOAD.MEAN counter to measure the mean CPU usage of an RMP in the measurement period. Itindicates the load and operating performance of the CPU on the RMP in the measurement period.

The VS.CPU.CPULOAD.MEAN counter measures the CPU load on each RMP subsystem.


If the RMP CPU load is greater than 50% during peak hours for three consecutive days in a week, a prewarning is required.

If the RMP CPU load is greater than 60% during peak hours for three consecutive days in a week, contact Huawei for technical support.

2.4 Interface Board CPU Load


RNC interface boards provide transmission ports and resources, process transport network messages, and exchange data between RNC boards and between the RNC and external devices.

These boards forward and process data for the Iub, Iu, and Iur interfaces. If one of the interface boards is overloaded, the packet loss rate increases. This affects communications and deteriorates user experience.

In effective mode, run the MML command LST BRD to query information about a specific board, for example, whetherthe board is an interface board.

In ineffective mode, find the MML command ADD BRD in the RNC configuration file. If the value of the BRDCLASS parameter is INT , the board is an interface board. You can obtain information about this interface board using thiscommand.


To obtain the interface board CPU load, monitor the control-plane CPU load and user-plane forwarding load.

The counters used to monitor the interface board CPU load are as follows:

VS.CPU.CPULOAD.MEAN: Average CPU Usage of the CPU

VS.INT.TRANSLOAD.RATIO.MEAN: Average Forwarding Ratio of Interface Boards

The forwarding load is expressed by the ratio of actual forwarding data rate to maximum forwarding data rate configured forthe interface board. The forwarding load indicates the operating load and performance of the interface board.

When the RNC detects that the CPU load on an interface board exceeds a specified threshold, ALM-20256 CPU Overload isreported.

If CIDs, UDPs, or TEIDs are overloaded on all interface boards of a certain type (for example, Iub interface boards),services cannot be established over the interface. To obtain the usages of CIDs, UDPs, or TEIDs, observe the followingcounters:

VS.INT.TRM.FLOW.UDP.MEAN: Average Number of Occupied UDP Ports of Interface Boards

VS.INT.TRM.FLOW.CID.MEAN: Average Number of Occupied CIDs of Interface Boards

VS.INT.TRM.FLOW.TEID.MEAN: Average Number of Occupied TEIDs of Interface Boards

VS.INT.TRM.FLOW.UDP.RESUSAGE.MEAN: Average Usage of UDP Ports of Interface Boards

VS.INT.TRM.FLOW.CID.RESUSAGE.MEAN: Average Usage of CID of Interface Boards

VS.INT.TRM.FLOW.TEID.RESUSAGE.MEAN: Average Number of Occupied TEIDs of Interface Boards

UDP: User Datagram Protocol

CID: Channel Identifier

TEID: Tunnel Endpoint ID


Perform capacity expansion in the following scenarios:

When the average CPU load on interface boards reaches 50%, prepare for capacity expansion. When the average CPU




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load on interface boards reaches 60%, perform capacity expansion immediately.

When the average forwarding load on interface boards reaches 70%, prepare for capacity expansion. When the averageforwarding load on interface boards reaches 80%, perform capacity expansion immediately.

When the average usage of CIDs, UDPs, or TEIDs on all interface boards of a certain type exceeds 70%, prepare forcapacity expansion. When the average usage of CIDs, UDPs, or TEIDs on all interface boards of a certain type exceeds85%, perform capacity expansion immediately.


In non-transmission resource pool networking scenarios, assess the capacity of each interface board. For loads betweeninterface boards of the same type, adjust the number of links carried on each interface board to balance loads between them.If loads are not balanced after the adjustment, add interface boards of the same type.

In transmission resource pool networking scenarios, if the load on an interface board in the resource pool exceeds the loadthreshold, add interface boards of the same type.

If the average CIDs, UDPs, or TEIDs on all interface boards of a certain type are overloaded, add interface boards of thesame type. You do not need to consider whether the scenario is transmission resource pool networking or non-transmissionresource pool networking.

For details about the Transmission Resource Pool in RNC feature, see Transmission Resource Pool in RNC FeatureParameter Description in the RAN feature documentation.

2.5 SCU CPU Load2.5.1 Monitoring Principles

Two SCU boards are installed each subrack. SCUb boards are permanently installed in slots 20 and 21 of each subrack. TwoSCU boards in the same subrack work in active/standby mode.

Ports on an SCU board form a trunk group that connects the MPS to the EPS. Restricted by their switching capacities, SCU boards are likely to be congested when configurations are unbalanced between subracks and when the inter-subrack traffic isheavy. When the traffic volume of inter-subrack communication approaches the overload threshold, voice service quality,data service quality, and network KPIs deteriorate, causing the system to become unstable. Therefore, the SCU CPU loadand inter-subrack bandwidth need to be monitored for SCU boards.


Monitoring of SCU CPU Load The VS.CPU.CPULOAD.MEAN counter monitors the SCU CPU load.

When the RNC detects that the CPU load of an SCU subsystem exceeds a specified overload threshold, ALM-20256 CPUOverload is reported. You can query the overload threshold by running the LST CPUTHD command.

Monitoring of Inter-Subrack Bandwidth

The counters used to monitor the inter-subrack bandwidth are as follows:

VS.Frame.Flux.Mean.TxRate: Average Inter-Subrack Transmitting Traffic

Frame Mean Usage: Average utility rate of inter-subrack traffic

The Frame Mean Usage is calculated using the following formula:

Frame Mean Usage = VS.Frame.Flux.Mean.TxRate/Inter-subrack bandwidth x 100%

When a pair of active and standby SCUb boards are configured, the inter-subrack bandwidth is 40 Gbit/s. If either the activeor standby SCUb board becomes faulty, the inter-subrack bandwidth is reduced by half.


When the SCU CPU load reaches 60%, contact Huawei for technical support.

If the value of Frame Mean Usage exceeds 40%, contact Huawei for technical support.

2.6 Common Channel Usage





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Common channels include paging channels (PCHs), forward access channels (FACHs), and random access channels(RACHs).

PCHs are downlink channels used to transmit paging messages. If the PCH usage is high, paging messages may be lost.

FACHs are downlink transmission channels and RACHs are uplink transmission channels. FACHs and RACHs transmitsignaling and a small amount of user data. RACH insufficiency will decrease the network access success rate and deteriorateuser experience. FACH insufficiency will cause a large number of state transitions for PS services, occurrence of RRCsignaling storms, and loss of signaling messages or user data.


Based on the RNC's default parameter settings, the usages of PCHs, FACHs, and RACHs are calculated using the followingformulas:

1. PCH usage

PCH usage = VS.UTRAN.AttPaging1/( x 60 x 5/0.01)

indicates the measurement period expressed in minutes.

2. FACH usage− If a secondary common control physical channel (SCCPCH) carries both a FACH and a PCH, the FACH usage iscalculated using the following formula:

Usage of an FACH carried on a non-standalone SCCPCH = VS.CRNCIubBytesFACH.Tx x 8/[(60 x x 168 x 1/0.01) xVS.PCH.Bandwidth.UsageRate x 6/7] + [(60 x x 360 x 1/0.01) x (1 - VS.PCH.Bandwidth.UsageRate x 6/7)]

where

VS.PCH.Bandwidth.UsageRate = /( x x 60)− If an SCCPCH only carries a FACH, the FACH usage is calculated using the following formula:

FACH Usage = ((VS.SRBNum.FACH - VS.OneSRBTTINum.FACH)/2 + VS.OneSRBTTINum.FACH +VS.IndepTRBNum.FACH)/( x 60/0.01)

3. RACH usage

Each cell has only one RACH. When signaling and user data coexist on the RACH, the RACH usage is calculated using thefollowing formula:

RACH Usage = ((VS.CRNCIubBytesRACH.Rx - VS.TRBNum.RACH x 360/8) x 8/168)/( x 60 x 4/0.02) +VS.TRBNum.RACH/( x 60 x 4/0.02)


It is recommended that you take the following measures to address PCH, FACH, and RACH overload:

PCH overload

Inappropriate LA planning will cause PCH overload because paging messages are broadcast across the entire LA.− If paging messages are not retransmitted, the paging message loss rate is 5% when the PCH usage reaches 60%. In thisscenario, analyze the cause of paging message loss or replan the LAs.− If paging messages are retransmitted once or twice, the paging message loss rate is 1% when the PCH usage reaches70%. In this scenario, analyze the cause of paging message loss or replan the LAs.

FACH overload

If the FACH usage reaches 70% during peak hours for three consecutive days in a week, the following measures arerecommended:− If the network is configured with only one SCCPCH, add a second SCCPCH to carry FACHs.− If SCCPCHs cannot be added, add carriers, NodeBs, or micro NodeBs.

RACH overload

If the RACH usage reaches 70% during peak hours for three consecutive days in a week, add carriers.

2.7 Downlink Load




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The downlink capacity of a cell is limited by its total available transmit power, which is determined by the NodeB poweramplifier's capability and the power configured for the cel l.

The downlink transmit power consists of the following, as shown in Figure 2-2:

Common channel (CCH) power

Non-HSPA power without CCHHSPA power

Power margin

Figure 2-2 Dynamic power resource allocation

Downlink power resources are allocated as follows:

1. Downlink power resources are first reserved for common physical channels and allocated to the DPCH. The remaining power resources are available for HSPA, including HSUPA and HSDPA.

2. The HSPA power resources are first allocated to the HSUPA downlink control channels, including the E-AGCH, E-RGCH, and E-HICH. The remaining power resources are available for HSDPA.

3. The HSDPA power resources are first allocated to the downlink control channel HS-SCCH. The remaining powerresources are available for the traffic channel HS-PDSCH.

Downlink power consumption is related to cell coverage, UE locations, and the traffic load in the cell. Large cell coverage,UEs being far away from the cell center, and heavy traffic load all contribute to large downlink power consumption.Therefore, downlink power overload is more likely to occur in hotspots or in cells with large coverage.

When the downlink transmit power is insufficient, the following occurs:

The cell coverage shrinks.

The data throughput decreases.

The service quality declines.

New service requests are likely to be rejected.


The following TCP-associated counters are defined for Huawei RNCs:

VS.MeanTCP: Mean Transmitted Power of Carrier for Cell

VS.MeanTCP.NonHS: Mean Non-HSDPA Transmitted Carrier Power for Cell

VS.HSDPA.MeanChThroughput: Mean Downlink Throughput of single HSDPA MAC-d Flows for Cell

The downlink cell load is indicated by the mean utility ratio of transmitted carrier power in a cell.

The mean utility ratio of the transmitted carrier power for non-HSPA users in a cell (including non-HSPA users on CCHs)is calculated using the following formula:

MeanTCP (NonHS) Usage = MeanNonHSTCP /MAXTXPOWER x 100%




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The mean utility ratio of the transmitted carrier power for all users in a cell is calculated using the following formula:

MeanTCP Usage = MeanTCP/MAXTXPOWER x 100%

To obtain MAXTXPOWER, run the LST UCELL command to query the value of the Max Transmit Power of Cell parameter, and convert the parameter value from the unit "0.1 dBm" to "watt."



The MeanTCP (NonHS) Usage is greater than 70% during peak hours for three consecutive days in a week.

The MeanTCP Usage is greater than 85% and the value of the VS.HSDPA.MeanChThroughput counter is less than thevalue required by subscribers during peak hours for three consecutive days in a week (for example, 300 kbit/s).


For cells with heavy traffic, add a carrier for the current sector if possible; add a NodeB or split the sector if the number of carriers in the sector reaches the maximum.

For cells with light traffic and poor coverage, add a NodeB.

2.8 Uplink Load


RTWP measures the uplink cell capability on WCDMA networks.

RTWP includes the following:

Background noise

Intra-system interference, including uplink signals sent by the UEs in the serving and neighboring cells

RF interference, including RF interference from an external source (for example, RF interference from another RAT orfrom equipment other than communication equipment) and intra-system RF interference (for example, intermodulation

interference produced by hardware components)The NodeB measures the RTWP on each receive channel in each cell. The cell RTWP obtained by the RNC is the linearaverage of the RTWPs measured on all receive channels in a cell under the NodeB. The RTWP indicates the interference toa NodeB and the signal strength on the RX port on the RF module.

The uplink cell capacity is restricted by the rise over thermal (RoT), which equals the RTWP minus the cell's backgroundnoise. The formula is as follows:

If there is no RF interference, the RoT is generated by intra-system interference. Under this condition, the RoT is used as acriterion to evaluate the uplink load.

The relationship between the RoT and the uplink load factor is as follows:

noise increase corresponds to 75% ofthe uplink load.

Figure 2-3 Relationship between RTWP, noise increase, and uplink load




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A large RTWP value in a cell is caused by traffic overflow, hardware faults (for example, poor quality of antennas or feederconnectors), or external interference. If the RTWP value is too large, the cell coverage shrinks, the quality of admitted services declines, or new service requests are rejected.


The RTWP and Equivalent Number of Users (ENU) are indicated by the following counters:

VS.MeanRTWP: Mean Power of Totally Received Bandwidth for Cell

VS.MinRTWP: Minimum Power of Totally Received Bandwidth for Cell

VS.RAC.UL.EqvUserNum: Mean Number of UL Equivalent Voice UEs in CELL_DCH State for Cell

UlTotalEqUserNum: total number of equivalent users in the uplink, which can be queried using the RNC MML commandLST UCELLCAC .

The UL ENU Ratio is calculated using the following formula:

UL ENU Ratio = VS.RAC.UL.EqvUserNum/UlTotalEqUserNum

In some areas, the background noise increases to -106 dBm or above due to external interference or hardware faults. If thisoccurs, the value of the VS.MinRTWP counter (the RTWP value obtained when the cell carries no traffic) is considered the

background noise.The RTWP of a cell is considered high when the value of the VS.MeanRTWP counter is greater than -100 dBm during off-

peak hours or greater than -90 dBm during peak hours for two or three consecutive days in a week.

A cell is considered heavily loaded if the UL ENU Ratio exceeds 75% during peak hours for two or three consecutive daysin a week.



If the value of the VS.MinRTWP counter is greater than -100 dBm or less than -110 dBm during off-peak hours for threeconsecutive days in a week, there may be hardware faults or external interference. Locate and rectify the faults and attemptto eliminate the interference.

The following table lists the RF alarms reported by the NodeB.

Alarm ID Alarm NameALM-26522 RF Unit RX Channel RTWP/RSSI Unbalanced ALM-26521 RF Unit RX Channel RTWP/RSSI Too LowALM-26532 RF Unit Hardware FaultALM-26752 ALD Hardware FaultALM-26758 TMA Running Data and Configuration MismatchALM-26755 TMA BypassALM-26757 RET Antenna Running Data and Configuration MismatchALM-26541 ALD Maintenance Link Failure




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If the value of the VS.MeanRTWP counter is greater than -90 dBm during peak hours for three consecutive days in aweek, there may be hardware faults or external interference. Locate and rectify the faults and attempt to eliminate theinterference. If the value of the VS.MeanRTWP counter is still greater than -90 dBm after hardware faults are rectified andexternal interference is eliminated, enable the following features as required:

− WRFD-140215 Dynamic Configuration of HSDPA CQI Feedback Period − WRFD-010712 Adaptive Configuration of Traffic Channel Power offset for HSUPA

If the uplink capacity of the cell still does not meet the requirements after the preceding features are enabled, add carriers. Ifthere are no additional UARFCNs available, add NodeBs.

For details about how to enable the WRFD-140215 Dynamic Configuration of HSDPA CQI Feedback Period feature, see Dynamic Configuration Based on the Uplink Load Feature Parameter Description in the RAN Feature Documentation.

For details about how to enable the WRFD-010712 Adaptive Configuration of Traffic Channel Power offset for HSUPAfeature, see Power Control Feature Parameter Description in the RAN Feature Documentation.

If the number of uplink ENUs is insufficient and the amount of uplink power is sufficient, run the MOD UCELLCACcommand with the UL total equivalent user number parameter set to a larger value. In addition, run the SETUADMCTRL command with the AF of hsupa interactive service and AF of hsupa background service parameters set to

10 .

2.9 OVSF Code Usage


In a WCDMA system, channels are identified by codes. Two types of codes are used for each channel. One is thescrambling code and the other is the Orthogonal Variable Spreading Factor (OVSF) code.

In the uplink, each UE is allocated a unique scrambling code. In the downlink, each cell is allocated a unique scramblingcode; all UEs in a cell use the same scrambling code but each of them is allocated a unique OVSF code. Therefore, OVSFcodes distinguish the downlink physical channels of different UEs in a cell.

In a WCDMA cell, different user data is distinguished by the CDMA technique, and all user data is transmitted over thesame central frequency almost at the same time. OVSF codes provide perfect orthogonality, minimizing interference

between different users.

Figure 2-4 shows an OVSF code tree.

Figure 2-4 OVSF code tree

In the downlink, the maximum spreading factor (SF) is 256.

An OVSF code tree can be divided into 4 SF4 codes, 8 SF8 codes, 16 SF16 codes, ..., 256 SF256 codes. Codes with variousSFs can be considered equivalent to SF256 codes. For example, a code with SF8 is equivalent to 32 codes with SF256.Using this method, the OVSF code usage can be calculated for a user or a cell.

In a cell, only one OVSF code tree is available. In the OVSF code tree, sibling codes are orthogonal to each other, but arenon-orthogonal to their parent or child codes. As a result, once a code is allocated to a user, neither its parent nor child codecan be allocated to any other user. Downlink OVSF code resources are limited. If available OVSF codes are insufficient, a

ALM-26529 RF Unit VSWR Threshold Crossed




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new call request is rejected.

After HSDPA is introduced, HSDPA and R99 services share OVSF codes. HS-PDSCH code resource management can be performed at both RNC and NodeB levels. RNC-controlled static or dynamic code allocation is enabled through theAllocate Code Mode parameter. NodeB-controlled dynamic code allocation is enabled through the DynCodeSw parameter.

Figure 2-5 shows RNC-controlled static code allocation.

Figure 2-5 RNC-controlled static code allocation

Figure 2-6 shows RNC-controlled dynamic code allocation.

Figure 2-6 RNC-controlled dynamic code allocation

The system reserves code resources for HSDPA services, and these code resources can be shared among HSDPA services.Therefore, HSDPA services do not require admission control based on cell code resources.

Figure 2-7 shows NodeB-controlled dynamic code allocation.

Figure 2-7 NodeB-controlled dynamic code allocation

NodeB-controlled dynamic code allocation is more flexible than RNC-controlled dynamic code allocation. It shortens theresponse time and saves the Iub signaling used for code allocation.


Huawei RNCs monitor the average usage of an OVSF code tree based on the number of equivalent codes with SF256, whichis measured by the VS.RAB.SFOccupy counter.

The codes available for the dedicated channel (DCH) can be calculated using the following formula:

DCH_OVSF_CODE = ( + ) x 64 + ( +) x 32 + ( + ) x 16 + ( +) x 8 + ( + ) x 4 + ( +) x 2 + ( + )

The maximum number of codes available for the DCH can be calculated using the following formula:

DCH_OVSF_CODE_Ava = 256 - (Codes occupied by CCHs + Codes occupied by E-AGCHs + Codes occupied by E-RGCHs and E-HICHs + Codes reserved for HS-PDSCHs + HS-SCCH codes)

For example, if the following conditions are met:

A cell that supports HSPA is configured with one SCCPCH, one E-AGCH, one E-RGCH/E-HICH, and two HS-SCCHs.

At least one code is reserved for HSDPA services.

Then, DCH_OVSF_CODE_Ava = 256 - (8 + 1 + 2 + 16 + 4) = 225.

OVSF code usages are calculated as follows:




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OVSF Usage= VS.RAB.SFOccupy/256 x 100%

DCH OVSF Usage = DCH_OVSF_CODE/DCH_OVSF_CODE_Ava


If the value of a cell's DCH OVSF Usage is greater than 70% during peak hours for three consecutive days in a week, thecell runs out of OVSF codes.

Perform capacity expansion as follows:Enable the WRFD-010631 Dynamic Code Allocation Based on NodeB feature if this feature has not been enabled.

Preferentially allocate idle codes to HSDPA UEs to improve the HSDPA UE throughput.

Add a carrier or split the sector.

Enable the WRFD-010653 96 HSDPA Users per Cell feature if it is not enabled.

For details about how to enable the WRFD-010631 Dynamic Code Allocation Based on NodeB feature and the WRFD-010653 96 HSDPA Users per Cell feature, see HSDPA Feature Parameter Description in the RAN Feature Documentation.

2.10 CE Usage


CE resources are baseband processing resources in a NodeB. The more CEs a NodeB supports, the stronger the NodeB'sservice processing capability. If a new call arrives but there are not enough CEs (not enough baseband processingresources), the call will be blocked.

Uplink CE resources can be shared in an uplink resource group, but not between uplink resource groups. Downlink CEresources are associated with the baseband processing boards where a cell is set up. CE resources allocated by licenses areshared among services on the NodeB. (CE resources are shared on a per operator basis in MOCN scenarios.)

The NodeB sends the RNC a response message that carries its CE capability. The NodeB's CE capability is limited by boththe installed hardware and the configured software licenses.

The methods of calculating the credit resource usage of admitted UEs are different before and after the CE Overbookingfeature is enabled. Table 2-3 describes the details.

Table 2-3 Credit resources consumed by admitted UEs before and after CE Overbooking is enabled

For details about CE Overbooking, see CE Overbooking Feature Parameter Description.

Before or After CE Overbooking isEnabled Credit Resource Consumed by Admitted UEs

Before CE Overbooking is enabled The RNC calculates the usage of CEs for admitted UEs by adding up creeach UE.

R99 UE: The RNC calculates the usage of credit resources for an R99 binding record (MBR).

HSUPA UE: The RNC calculates the usage of credit resources for an(GBR, Rateone RLC PDU).

After CE Overbooking is enabled The NodeB calculates the usage of credit resources for all admitted UEsand periodically reports the calculation results to the RNC through meas

R99 UE: The NodeB calculates the usage of credit resources for an R9HSUPA UE using a 10 ms transmission time interval (TTI): The Nod

usage of such a UE based on the UE's rate. After the adjustment, the csuch a UE must not exceed the credit resources required by Rate one RLC

HSUPA UE using a 2 ms TTI: The NodeB adjusts the credit resource

the UE's rate and the minimum number of CEs (specified by CERSV admitting such a UE. After the adjustment, the credit resources consuexceed the credit resources required by Rate one RLC PDU .

The minimum number of CEs reserved for admitting an HSUPA Udefault. The value range is 1 to 8.




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CCHs do not require extra CE resources because the RNC reserves CE resources for services on these channels. Signalingcarried on an associated channel of the DCH does not consume extra CE resources, either. One CE can be consumed by a12.2 kbit/s voice call.

HSDPA services do not consume downlink CEs allocated to R99 services. HSUPA and R99 services share uplink CEs.

For details about CE number consumed by different services, see CE Resource Management Feature Parameter Description.


The following RNC counters are used to monitor CE usage:

VS.NodeB.ULCreditUsed.Mean: Average NodeB Uplink Credit Usage When CE Overbooking Is Enabled for NodeB

VS.LC.ULCreditUsed.Mean: Mean Usage of UL Credit for Cell

VS.LC.DLCreditUsed.Mean: Mean Usage of DL Credit for Cell

The NodeB uses separate baseband processing units in the uplink and downlink. Therefore, the NodeB manages uplink anddownlink CE resources separately. The uplink and downlink CE resource usages are calculated as follows:

License-based uplink CE usage

License-based uplink CE usage = UL NodeB Mean CE Used Number/UL License CE Number

If the value of the VS.NodeB.ULCreditUsed.Mean counter is greater than 0, the CE Overbooking feature has taken effect,and the following formula is true:

UL NodeB Mean CE Used Number = VS.NodeB.ULCreditUsed.Mean/2

Otherwise, the following formula is true:

UL NodeB Mean CE Used Number = Sum_AllCells_of_NodeB(VS.LC.ULCreditUsed.Mean/2)

where

"VS.LC.ULCreditUsed.Mean/2" indicates the number of uplink CEs because the number of uplink credit resources is twicethe number of uplink CEs, whereas the number of downlink credit resources is equal to the number of downlink CEs.

UL License CE Number = UL NodeB License CE Cfg Number

License-based downlink CE usage

License-based downlink CE usage = DL NodeB Mean CE Used Number/DL License CE Number

DL NodeB Mean CE Used Number = Sum_AllCells_of_NodeB(VS.LC.DLCreditUsed.Mean)

DL License CE Number = DL NodeB License CE Cfg Number Hardware-based uplink CE usage

Hardware-based uplink CE usage = UL NodeB Mean CE Used Number/UL CE Capacity Number

The value of UL NodeB Mean CE Used Number equals that used for calculating the license-based uplink CE usage.

UL CE Capacity Number = VS.HW.ULCreditAvailable

Hardware-based downlink CE usage

Hardware-based downlink CE usage = DL NodeB Mean CE Used Number/DL CE Capacity Number

The value of DL NodeB Mean CE Used Number equals that used for calculating the license-based downlink CE usage.

DL CE Capacity Number = VS.HW.DLCreditAvailable

The CE resource usage can be monitored by alarms. If the CE hardware capacity is exceeded, ALM-28230 Base StationService Overload is reported.


If the uplink/downlink license- or hardware-based CE usage is consistently greater than 70% during peak hours for threeconsecutive days in a week, perform capacity expansion as follows:

If the license-based CE usage exceeds its capacity expansion threshold, CE resources are limited by the license. In thissituation, upgrade the license file.

If the hardware-based CE usage exceeds the capacity expansion threshold, CE resources are limited by the hardwarecapacity. In this situation, add WBBP boards.

If capacity expansion is inapplicable, perform the following operations:




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Run the RNC MML command SET UCORRMALGOSWITCH . In this step, select the DRA_DCCC_SWITCH and DRA_BASE_ADM_CE_BE_TTI_RECFG_SWITCH check boxes under the Dynamic Resource Allocation Switch

parameter to enable the DCCC algorithm and the TTI dynamic adjustment algorithm for admission CE-based BE services,respectively.

Run the RNC MML command SET UUSERGBR with the Uplink GBR for BE service parameter set to D32 .

Newly added CE resources can share the traffic in hotspots and relieve CE congestion caused by traffic overflow.

2.11 Iub Bandwidth Usage


The Iub interface exists between the NodeB and RNC. The interface uses ATM or IP transmission depending on thetransmission medium.

ATM and IP transmission resources can be classified into physical resources, logical port (LP) resources, resource groups,and link resources, as shown in Figure 2-8 and Figure 2-9.

Figure 2-8 ATM transmission resources

Figure 2-9 IP transmission resources

In IP transmission, the BSC6910 only support transmission resource pool mode and does not support resource groups.

Iub bandwidth congestion will cause RRC connection setup and RAB setup failures. Table 2-10 describes Iub bandwidthcongestion scenarios.

Table 2-4 Iub bandwidth congestion scenarios




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ATM Transmission

On an ATM transport network, Huawei RNCs and NodeBs can monitor the uplink and downlink load on their interface boards. The Iub bandwidth usage is indicated by the ratio of the actual uplink or downlink load to the configured Iub bandwidth.

The RNC monitors the bandwidth-based admission success rate for each NodeB.

1. Bandwidth-based admission success rate

The counters used to measure the bandwidth-based admission success rate are as follows:VS.AAL2.CAC.Succ: Number of Successful AAL2 Path Admissions

VS.AAL2.CAC.Att: Number of AAL2 Path Resource Admissions

The bandwidth-based admission success rate is calculated using the following formula:

Bandwidth-based admission success rate = VS.AAL2.CAC.Succ/VS.AAL2.CAC.Att

If the bandwidth-based admission success rate is less than 99%, bandwidth congestion has probably occurred on the user plane.

2. Physical bandwidth usage

(1) Control plane

The counters for monitoring the number of bytes transmitted or received on a Signaling ATM Layer (SAAL) link (carrying NCP, CCP, and ALCAP) are as follows:

VS.SAALLNK.PVCLAYER.TXBYTES: Number of bytes transmitted on an SAAL link at the ATM layer VS.SAALLNK.PVCLAYER.RXBYTES: Number of bytes received on an SAAL link at the ATM layer

The uplink and downlink bandwidth usages of the SAAL links on the control plane over the Iub interface are calculatedusing the following formulas:

UL Iub Usage on Control Plane = VS.SAALLNK.PVCLAYER.RXBYTES x 8/1000//RX BW_CFG

DL Iub Usage on Control Plane = VS.SAALLNK.PVCLAYER.TXBYTES x 8/1000//TX BW_CFG

When the uplink or downlink bandwidth usage reaches 70%, bandwidth congestion may have occurred on the control plane.Then, capacity expansion is required. In addition, if ALM-21532 SAAL Link Congestion is reported on the Iub interface,

bandwidth congestion has occurred on the control plane.

(2) User plane

The counters for measuring the number of bytes transmitted or received on an AAL2 path at the ATM layer for NodeBs areas follows:

VS.AAL2PATH.PVCLAYER.TXBYTES: Number of bytes transmitted on an AAL2 path at the ATM layer VS.AAL2PATH.PVCLAYER.RXBYTES: Number of bytes received on an AAL2 path at the ATM layer

The uplink and downlink bandwidth usages of the user plane on the Iub interface are calculated using the followingformulas:

UL Iub Usage on User Plane = Sum (VS.AAL2PATH.PVCLAYER.RXBYTES) x 8//1000/RX BW_CFG

DL Iub Usage on User Plane = Sum (VS.AAL2PATH.PVCLAYER.TXBYTES) x 8//1000/TX BW_CFG

When the uplink or downlink bandwidth usage reaches 70%, bandwidth congestion has occurred on the user plane. Then,capacity expansion is required.

Scenario DescriptionThe physicaltransmission resourcesare sufficient, but theadmission fails.

Admission control is performed based on the sufficiencyof transmission resources. If transmission resources aresufficient, the admission succeeds. Otherwise, thetransmission fails. Admission control prevents excessiveservice admission and ensures the quality of admitted services.

The physicaltransmission bandwidthis insufficient.

The physical transmission bandwidth between the RNCand NodeB is insufficient.




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IP Transmission

On an IP transmission network, the RNC and NodeB can monitor the average uplink and downlink loads on their interface boards. The Iub bandwidth usage is represented by the ratio of the average uplink or downlink load to the configured Iub bandwidth. In addition, the RNC and NodeB can dynamically adjust the bandwidth of a service based on the QoSrequirements of the service and user priority and improve the Iub bandwidth usage using the reserve pressure algorithm ontheir interface boards.

1. Bandwidth-based admission success rate

The counters for monitoring the bandwidth-based admission success rate are as follows:

VS.ANI.IP.Conn.Estab.Succ: Number of Successful IP Connections for IP Transport Adjacent Node

VS.ANI.IP.Conn.Estab.Att: Number of IP Connection Setup Requests Received by IP Transport Adjacent Node

VS.ANI.IP.FailResAllocForBwLimit: Number of Failed Resource Allocations Due to Insufficient Bandwidth on the IPTransport Adjacent Node

The IP connection setup success rate is calculated using the following formula:

IP connection setup success rate = VS.ANI.IP.Conn.Estab.Succ/VS.ANI.IP.Conn.Estab.Att

If the IP connection setup success rate is less than 99%, bandwidth congestion has probably occurred on the user plane.

If the value of the VS.ANI.IP.FailResAllocForBwLimit counter is not zero, bandwidth congestion has occurred on the user plane.

2. Physical bandwidth usage

(1) Control plane

The counters for monitoring the number of bytes transmitted or received on an SCTP link (carrying NCP, CCP, andALCAP) are as follows:

VS.SCTP.TX.BYTES: Number of IP bytes transmitted on an SCTP link

VS.SCTP.RX.BYTES: Number of IP bytes received on an SCTP link

The uplink and downlink traffic volumes of the SCTP links on the control plane over the Iub interface are calculated usingthe following formulas:

SCTP UL KBPS = VS.SCTP.RX.BYTES x 8//1000

SCTP DL KBPS = VS.SCTP.TX.BYTES x 8//1000

If ALM-21542 SCTP Link Congestion is reported on the Iub interface, bandwidth congestion has occurred on the control plane.

(2) User planeIn transmission resource pool networking, the number of IP bytes transmitted or received on the user plane by each adjacentnode is measured by the following counters:

VS.IPPOOL.ANI.IPLAYER.TXBYTES: Number of IP bytes transmitted on the user plane of an adjacent node

VS.IPPOOL.ANI.IPLAYER.RXBYTES: Number of IP bytes received on the user plane of an adjacent node

The Iub bandwidth usage of a transmission resource pool is calculated using the following formulas:

UL Iub Usage on User Plane = VS.IPPOOL.ANI.IPLAYER.RXBYTES x 8//1000/RX BW_CFG

DL Iub Usage on User Plane = VS.IPPOOL.ANI.IPLAYER.TXBYTES x 8//1000/TX BW_CFG

If the uplink or downlink bandwidth usage of the user plane on the Iub interface reaches 70%, bandwidth congestion hasoccurred on the user plane. Then, capacity expansion is required.


If the Iub bandwidth usage exceeds 70% during peak hours for three consecutive days in a week, the Iub bandwidth isinsufficient.

No. Scenario Optimization Suggestion1 Bandwidth congestion on the ATM control

planeIncrease the bandwidth configthe SAAL link.

2 Bandwidth congestion on the IP control plane

Increase the t ransmiss ion banfor the SCTP link.

3 Physical bandwidth congestion on the ATMand IP user planes

Increase the transmission ban




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Scenario 1: Bandwidth Congestion on the ATM Control Plane

If an SAAL link is congested, increase the bandwidth configured for the SAAL link by running the following commands:

ADD ATMTRF: TRFX= NewIndex , ST=NRTVBR, UT=KBIT/S, PCR= NewValue , SCR= NewValue ;MOD SAALLNK: SRN=XXX, SN=XXX, SAALLNKN=XXX, CARRYT=IMA, CARRYSRN=XXX,CARRYSN= NewIndex , CARRYIMAGRPN= NewIndex ;

Scenario 2: Bandwidth Congestion on the IP Control Plane

If an SCTP link is congested, check whether the transmission bandwidth between the RNC and NodeB is sufficient andwhether the DSCP of the SCTP link is appropriately set. If the transmission bandwidth is sufficient and the DSCP isappropriately set, add an SCTP link by running the following command:

ADD SCTPLNK: SRN=XXX, SN=XXX, SCTPLNKN=XXX, MODE=SERVER, APP=NBAP, DSCP=48 ,VLANFLAG1=DISABLE, VLANFLAG2=DISABLE, SWITCHBACKFLAG=YES ;

Scenario 3: Physical Bandwidth Congestion on the ATM and IP User Planes

Increase the physical bandwidth of the Iub interface as required.

Scenario 4: Admission Bandwidth Congestion on the ATM and IP User Planes, Not Accompanied by Physical BandwidthCongestion

4 Admission bandwidth congestion on theATM and IP user planes, not accompanied

by physical bandwidth congestion

Decrease the activity factor foservices.

Step 2 Decrease the activity factor for PS services to enable the system to admit more UEs. Query the activity factor used by theadjacent node by checking the configuration data of the following command:

ADD ADJMAP: ANI=XXX, ITFT=IUB, TRANST=XXX, CNMNGMODE=SHARE, FTI= OldIndex ;

Step 3 Run the ADD TRMFACTOR command to add an activity factor table. The recommended value for PSINTERDL,PSINTERUL, PSBKGDL, PSBKGUL, HDINTERDL , and HDBKGDL is 10 . The following is an example:

ADD TRMFACTOR:FTI= NewIndex , REMARK="IUB_USER", PSINTERDL= 10, PSINTERUL= 10, PSBKGDL= 10,PSBKGUL= 10 , HDINTERDL= 10, HDBKGDL= 10;

Step 4 Run the MOD ADJMAP command to use the new activity factor on the adjacent node. The following is an example:

MOD ADJMAP: ANI=XXX, ITFT=IUB, FTI= NewIndex ;

The activity factor equals the ratio of actual bandwidth occupied by a UE to the bandwidth allocated to the UE during itsinitial access. It is used to predict the bandwidth required by admission. Each NodeB can be configured with its own activityfactor. The default activity factor for voice services is 70%, and the default activity factor for PS BE services is 40%.

----End

2.12 NodeB CNBAP Load


CNBAP load is used to assess a NodeB's processing capability. CNBAP overload will cause a radio link setup failure,thereby decreasing the RRC connection setup and RAB setup success rates.


The following NodeB counters are used to monitor the CNBAP load:

VS.RadioLink.Recv.Mean: average number of wireless connection receptions per second

VS.DedicMeaRpt.MEAN: average number of Dedicated Measurement Reporting per second

VS.BTS.CnbapCap.UseRate: Average CNBAP ratio of the NodeB

The CNBAP load on a NodeB is limited by the license and hardware capacity. The license- and hardware-based CNBAPusages are calculated using the following formulas:

License-based CNBAP Usage = (VS.RadioLink.Recv.Mean + VS.DedicMeaRpt.MEAN/12)/License CNBAP

where License CNBAP = NodeB License CNBAP Cfg Number




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Hardware-based CNBAP Usage = VS.BTS.CnbapCap.UseRate

CNBAP resource usage can be monitored by alarms. If the CNBAP hardware capacity is exceeded, ALM-28230 BaseStation Service Overload is reported.


If the license- or hardware-based CNBAP usage on the NodeB is greater than 60% during peak hours for three consecutive

days in a week, the NodeB is considered overloaded.Perform capacity expansion as follows:

Enable the WRFD-010202 UE State in Connected Mode (CELL_DCH, CELL_PCH, URA_PCH, CELL_FACH) andWRFD-020500 Enhanced Fast Dormancy features.

If the license-based CNBAP usage exceeds its capacity expansion threshold, CNBAP resources are limited by the license.In this situation, upgrade the license file.

If the hardware-based CNBAP usage exceeds its capacity expansion threshold, CNBAP resources are limited by thehardware. In this situation, replace the WMPT board with the UMPT board, add baseband processing boards, or replace

baseband processing boards with those of higher specifications.

Split the NodeB or add a NodeB if the CNBAP overload problem cannot be solved by upgrading the license file or byadding or replacing boards.

For details about how to enable the WRFD-010202 UE State in Connected Mode (CELL_DCH, CELL_PCH, URA_PCH,CELL_FACH) feature, see State Transition Feature Parameter Description in the RAN Feature Documentation.

For details about how to enable the WRFD-020500 Enhanced Fast Dormancy feature, see Enhanced Fast DormancyFeature Parameter Description in the RAN Feature Documentation.

The maximum CNBAP capability of a NodeB is 1500. When the CNBAP capability configured for a NodeB is less than1500, replace boards to expand the capacity if CNBAP overload occurs. For the CNBAP capabilities of the WBBP boards,see 3900 Series Base Station Technical Description .

2.13 HSPA Users


HSPA services are mainly carried on the WBBP or UBBP boards in a NodeB. Therefore, the number of HSPA users

determines WBBP board loads. If WBBP boards are overloaded with HSPA users, new users may fail to access the network.


The following NodeB counters are used to monitor the percentage of the number of HSPA users on a WBBP or UBBP board to the configured number of HSPA users:

VS.BOARD.UsedHsdpaUserRatio.Mean: average ratio of HSDPA users on a board

VS.BOARD.UsedHsupaUserRatio.Mean: average ratio of HSUPA users on a board


If the percentage of the number of HSDPA/HSUPA users on a WBBP or UBBP board to the configured number ofHSDPA/HSUPA users is greater than 60% during peak hours for three consecutive days in a week, perform capacityexpansion as follows:

Enable the WRFD-150242 HSDPA Scheduler Pool feature if VS.BOARD.UsedHsdpaUserRatio.Mean is greater than60% only on individual WBBP boards.

Add WBBP boards or replace the existing WBBP or UBBP boards with those of higher specifications.

Split the NodeB or add a NodeB if no more WBBP or UBBP boards can be added.

For details about how to enable the WRFD-150242 HSDPA Scheduler Pool feature, see HSDPA Scheduler Pool FeatureParameter Description in the RAN feature documentation.

The number of HSPA users supported by a WBBP or UBBP board varies according to the board type. For detailed




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numbers of HSPA users supported by different WBBP boards, see 3900 Series Base Station Technical Description .




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3 Network Resource TroubleshootingThe monitoring method described in chapter 2 "Network Resource Monitoring" is effective in most scenarios. However,other scenarios may require more detailed troubleshooting to determine if high resource occupancy is caused by trafficincreases or other abnormalities.

This chapter describes how to locate network resource problems that require more detailed troubleshooting and is intendedfor personnel who:

Have a deep understanding of WCDMA networks

Are familiar with the signaling procedure

Are familiar with the operation and maintenance of Huawei products

3.1 Possible Block and Failure Points in the Basic Call Flow

When network resources are insufficient, accessibility-related KPIs are likely to be affected first.

Figure 3-1 uses a mobile terminated call (MTC) as an example to illustrate the basic cal l flow, with possible block/failure points indicated. For details about the basic call process, see 3GPP TS 25.931.

Figure 3-1 Basic call flow chart and possible block/failure points




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The basic call flow illustrated in Figure 3-1 is described as follows:

Step 1 The CN sends a paging message to the RNC.

Step 2 Upon receiving the paging message, the RNC broadcasts the message on a PCH. If the PCH is congested, the RNC maydrop the message at block point #1.

Step 3 The UE may not receive the paging message or access the network, and fails to respond to RNC's paging message. Seefailure point # 2.

Step 4 If the UE receives the paging message, it sends an RRC connection setup request to the RNC.

Step 5 If the RNC is congested when receiving the RRC connection setup request, the RNC may drop the request message. See block point #3.

Step 6 If the RNC receives the RRC connection setup request and does not discard it, the RNC determines whether to accept orreject the request. The request may be rejected due to insufficient resources, as shown in block point #4.

Step 7 If the RNC accepts the request, the RNC instructs the UE to set up an RRC connection. The UE may not receive RNC'sresponse message or may find that the configuration does not support RRC connection setup. See failure points #5 and #6.

Step 8 After the RRC connection is set up, the UE sends NAS messages to negotiate with the CN about service setup. If the CNdetermines to set up a service, the CN sends an RAB assignment request to the RNC.

Step 9 The RNC accepts or rejects the RAB assignment request based on the resource usage of RAN. See block point #7.

Step 10 If the RNC accepts the RAB assignment request, it initiates an RB setup process. During the process, the RNC sets upradio links (RLs) to the NodeB over the Iub interface and sends an RB setup message to the UE over the Uu interface. TheRL or RB setup process may incur failures. See failure points #8 and #9.

----End

3.2 Counters Related to Call Congestion

As shown in Figure 3-1, call congestion may occur during paging, RRC connection setup, or RAB setup. This sectiondescribes counters related to call congestion. For details about these counters, see Chapter 4 "Metrics Definitions."

3.2.1 Paging Loss

The counters measuring RNC- and cell-level paging loss are as follows:

RNC-level paging loss

The counters measuring paging loss caused by Iu-interface flow control, CPU overload, or RNC-level PCH congestion areas follows:− VS.RANAP.CsPaging.Loss: number of failed responses after the RNC receives CS paging messages from the CN− VS.RANAP.PsPaging.Loss: number of failed responses after the RNC receives PS paging messages from the CN− VS.RANAP.CsPaging.Att: number of CS paging messages received by the RNC from the CN− VS.RANAP.PsPaging.Att: number of PS paging messages received by the RNC from the CN

Calculation formula:

IU Paging Congestion Ratio (RNC) = [(VS.RANAP.CsPaging.Loss + VS.RANAP.PsPaging.Loss)/(VS.RANAP.CsPaging.Att + VS.RANAP.PsPaging.Att)] x 100%

Cell-level paging loss

The counters measuring paging loss caused by cell-level PCH congestion are as follows:− VS.RRC.Paging1.Loss.PCHCong.Cell: number of discarded paging messages due to PCH congestion in a cell− VS.UTRAN.AttPaging1: number of paging messages of paging type 1 sent by the RNC in a cell

Calculation formula:

Iu-interface paging loss ratio (cell) = (VS.RRC.Paging1.Loss.PCHCong.Cell/VS.UTRAN.AttPaging1) x 100%

3.2.2 RRC Congestion

The following table describes the mapping between reasons of RRC connection setup rejections and corresponding counters.




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The RRC block rate is calculated using the following formula:

Vs.RRC.Block.Rate =Total RRC Rej/ VS.RRC.AttConnEstab.Sum x 100%

where

Total RRC Rej = < VS.RRC.Rej.ULPower.Cong > + < VS.RRC.Rej.DLPower.Cong > + < VS.RRC.Rej.ULCE.Cong > +< VS.RRC.Rej.DLCE.Cong > + < VS.RRC.Rej.ULIUBBand.Cong > + < VS.RRC.Rej.DLIUBBand.Cong > + <VS.RRC.Rej.Code.Cong >

VS.RRC.AttConnEstab.Sum: Number of Processed RRC Connection Requests for Cell

3.2.3 RAB Congestion

The following table describes the mapping between reasons of RAB setup rejections and corresponding counters.

The RAB block rate is calculated using the following formula:

Rejection Reason CounterUplink power congestion VS.RRC.Rej.ULPower.Cong: Number of RRC Connection

Rejects for Cell (UL Power Congestion)Downlink power congestion

VS.RRC.Rej.DLPower.Cong: Number of RRC ConnectionRejects for Cell (DL Power Congestion)

Uplink CE resourcecongestion

VS.RRC.Rej.ULCE.Cong: Number of RRC Connection Rejectsfor Cell (UL CE Resource Congestion)

Downlink CE resourcecongestion VS.RRC.Rej.DLCE.Cong: Number of RRC Connection Rejectsfor Cell (DL CE Resource Congestion)Uplink Iub bandwidthresource congestion

VS.RRC.Rej.ULIUBBand.Cong: Number of RRC ConnectionRejects for Cell (UL Iub Bandwidth Congestion)

Downlink Iub bandwidthresource congestion

VS.RRC.Rej.DLIUBBand.Cong: Number of RRC ConnectionRejects for Cell (DL Iub Bandwidth Congestion)

Downlink code resourcecongestion

VS.RRC.Rej.Code.Cong: Number of RRC Connection Rejectsfor Cell (Code Resource Congestion)

Rejection Reason CounterPower congestion VS.RAB.FailEstabCS.ULPower.Cong: Number of Failed CS

RAB Establishments for Cell (UL Power Congestion)VS.RAB.FailEstabCS.DLPower.Cong: Number of Failed CS

RAB Establishments for Cell (DL Power Congestion)VS.RAB.FailEstabPS.ULPower.Cong: Number of Failed PS RAB

Establishments for Cell (UL Power Congestion)VS.RAB.FailEstabPS.DLPower.Cong: Number of Failed PS RABEstablishments for Cell (DL Power Congestion)

Uplink CE congestion VS.RAB.FailEstabCS.ULCE.Cong: Number of Failed CS RABEstablishments for Cell (UL CE Congestion)

VS.RAB.FailEstabPS.ULCE.Cong: Number of Failed PS RABEstablishments for Cell (UL CE Congestion)

Downlink CEcongestion

VS.RAB.FailEstabCs.DLCE.Cong: Number of Failed CS RABEstablishments for Cell (DL CE Congestion)

VS.RAB.FailEstabPs.DLCE.Cong: Number of Failed PS RABEstablishments for Cell (DL CE Congestion)

Downlink coderesource congestion

VS.RAB.FailEstabCs.Code.Cong: Number of Failed CS RABEstablishments for Cell (Code Congestion)

VS.RAB.FailEstabPs.Code.Cong: Number of Failed PS RABEstablishments for Cell (Code Congestion)

Iub bandwidthcongestion VS.RAB.FailEstabCS.DLIUBBand.Cong: Number of Failed CSRAB Establishments for Cell (DL Iub Bandwidth Congestion)VS.RAB.FailEstabCS.ULIUBBand.Cong: Number of Failed CS

RAB Establishments for Cell (UL Iub Bandwidth Congestion)VS.RAB.FailEstabPS.DLIUBBand.Cong: Number of Failed PS

RAB Establishments for Cell (DL Iub Bandwidth Congestion)VS.RAB.FailEstabPS.ULIUBBand.Cong: Number of Failed PS

RAB Establishments for Cell (UL Iub Bandwidth Congestion)




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VS.RAB.Block.Rate = Total number of failed RAB establishments regardless of the cause of failure/VS.RAB.AttEstab.Cell

where VS.RAB.AttEstab.Cell measures the total number of RAB setup requests in a cell. This counter is calculated asfollows:

VS.RAB.AttEstab.Cell = VS.RAB.AttEstabCS.Conv + VS.RAB.AttEstabCS.Str + VS.RAB.AttEstabPS.Conv +VS.RAB.AttEstabPS.Bkg + VS.RAB.AttEstabPS.Int + VS.RAB.AttEstabPS.Str

3.3 Resource Usage Analysis

Figure 3-2 illustrates the general troubleshooting procedure for resource usage issues.

Figure 3-2 General troubleshooting procedure for resource usage issues

In most cases, the troubleshooting procedure includes detecting abnormal KPIs, selecting top N cells, and analyzingabnormal KPIs.

In the case of system bottlenecks, accessibility-related KPIs are usually checked first because most of the access congestionissues are caused by insufficient system resources.

Figure 3-3 shows key points for bottleneck analysis. The following sections then describe these key points.

Figure 3-3 Key points for bottleneck analysis




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3.3.1 CP CPU Load Analysis

Current networks are generally vulnerable to signaling storms caused by smartphones, and the CP's signaling processingcapability is most likely to become the system bottleneck.

If the CP CPU load exceeds the predefined alarm threshold, the RNC starts flow control to discard some RRC connectionsetup requests or paging requests. From the perspective of maintenance, the CP CPU load must be less than the alarmthreshold to guarantee system safety.

Figure 3-4 illustrates the procedure for analyzing the CP CPU load.

Figure 3-4 Procedure for analyzing the CP CPU load




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As shown in Figure 3-4, if the CP CPU load exceeds 50%, analyze the cause of the problem and prevent the CPU load fromincreasing further. In addition, perform an in-depth analysis of the high CPU load, for example, check whether the parameterconfigurations are appropriate. If the high CPU load is caused by an increase in traffic volume, it is recommended that youexpand hardware capacity.

CP/UP flexible deployment can adjust the hardware resources in the CP and UP pools so that these pools have basically thesame average load. Because the non-pooled load in the CP cannot be shared, dynamic cell allocation is required to balancethis load in the CP pool.

If the traffic model changes, the load can be balanced between CP and UP pools to a certain degree but cannot becompletely balanced. For example, if the CP CPU load is lower than the UP CPU load but the remaining CP resources areinsufficient to bear new NodeBs and cells, it is recommended that you reduce the number of cells in the RNC or add new

boards.

3.3.2 UP CPU Load Analysis

If the load on the EGPUa board or interface board is too high, the RNC discards some user-plane data. Figure 3-5 illustratesthe procedure for analyzing the UP CPU load.

Figure 3-5 Procedure for analyzing the UP CPU load




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If the UP CPU load exceeds 60%, analyze the cause of the problem and prevent the CPU load from increasing further. If the

high CPU load is caused by an increase in traffic volume, it is recommended that you expand hardware capacity.

3.3.3 CE Resource Analysis

Both CE congestion and CE resource monitoring require CE resource analysis. If CE usage remains greater than the presetoverload threshold or if CE congestion occurs, CE resources are insufficient and must be increased to ensure systemstability.

Figure 3-6 illustrates the procedure for analyzing CE congestion.

Figure 3-6 Procedure for analyzing CE congestion




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CE resources can be shared within a resource group. Therefore, CE usage on the NodeB must be calculated to determinewhether CE congestion occurs in a resource group or the NodeB. If CE congestion occurs in a resource group, reallocate CEresources among resource groups. If CE congestion occurs in the NodeB, perform capacity expansion.

3.3.4 Iub Resource Analysis

Figure 3-7 illustrates the procedure for analyzing Iub bandwidth congestion.

Figure 3-7 Procedure for analyzing Iub bandwidth congestion




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3.3.5 Power Resource Analysis

If the uplink RTWP and downlink TCP values are greater than the preset thresholds, power congestion occurs.

If power congestion occurs in the downlink, enable the load reshuffling (LDR) and overload control (OLC) functions. If power congestion occurs in the uplink, analyze whether the problem is caused by interference or traffic increases.

If the RTWP value remains greater than -97 dBm, identify root causes and troubleshoot the problem.

If the problem is caused by heavy traffic instead of signaling storms, perform the following operations:

Enable LDR and OLC for temporary troubleshooting.

Add carriers or split cells for a long-term solution.

Figure 3-8 illustrates the procedure for analyzing power resource usage.

Figure 3-8 Procedure for analyzing power resource usage




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Generally, adding a carrier is the most effective means of relieving uplink power congestion. If no additional carrier isavailable, add a NodeB or reduce the downtilt of the antenna.

3.3.6 PCH Usage Analysis

In most cases, PCHs are overloaded because an LA covers too many cells. Replan LAs to resolve the PCH overload.

Figure 3-9 illustrates the procedure for analyzing PCH usage.

Figure 3-9 Procedure for analyzing PCH usage




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3.3.7 FACH Usage Analysis

FACH congestion is less likely to occur when UE state transition is disabled. However, the RNC usually enables UE statetransition to transfer low-traffic services to FACHs. This saves radio resources but increases traffic on FACHs.

Methods of relieving FACH congestion are as follows:

Shorten the period during which PS services are carried on FACHs to enable fast UE state transition to the CELL_PCHstate or idle mode. In addition, set up RRC connections on DCHs if DCH resources are sufficient.

Add an SCCPCH to carry FACHs.

Figure 3-10 illustrates the procedure for analyzing FACH usage.

Figure 3-10 Procedure for analyzing FACH usage




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4 Metrics DefinitionsMetric Name Counter Description

Congestion-related MetricsCall Block Ratio Vs.Call.Block.Rate (customized) Vs.RRC.Block.Rate +

( /( +

)) xVs.Rab.Block.Rate

RRC CongestionRatio

Vs.RRC.Block.Rate (customized) ( + +

+ +

+ +

)/RAB Congestion

Ratio

Vs.RAB.Block.Rate (customized) ( +

+ + +

+ + + + + +

+

+

+

)/(VS.RAB.AttEstabCS.Conv +

VS.RAB.AttEstabCS.Str +VS.RAB.AttEstabPS.Conv +VS.RAB.AttEstabPS.Bkg +VS.RAB.AttEstabPS.Int +

VS.RAB.AttEstabPS.StrRAB)Call Attempts VS.RAB.AttEstab.Cell (customized) ( +

+ +

+ +)

Power Usage-related MetricsMeanTCP

(NonHS) UsageVS.MeanTCP.NonHS

where MAXTXPOWER is the maximum power configured for a cell. Measured in

watts.MeanTCP Usage VS.MeanTCP

where MAXTXPOWER is the maximum power configured for a cell. Measured in

watts.Mean UL RTWP VS.MeanRTWP VS.MeanRTWPMin UL RTWP VS.MinRTWP VS.MinRTWPUL ENU Rate VS.RAC.UL.EqvUserNum VS.RAC.UL.EqvUserNum/UlTotalEqUserNum




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Iub Interface Resource Usage-related MetricsAAL2 PATH

AdmissionSuccess Rate

VS.AAL2.CAC.SuccVS.AAL2.CAC.Att

VS.AAL2.CAC.Succ/VS.AAL2.CAC.Att

DL Iub Usage onControl Plane

VS.SAALLNK.PVCLAYER.TXBYTESVS.SAALLNK.PVCLAYER.RXBYTES

DL Iub Usage on Control Plane =VS.SAALLNK.PVCLAYER.TXBYTES x

8/1000//TX BW_CFGUL Iub Usage on

Control PlaneUL Iub Usage on Control Plane =

VS.SAALLNK.PVCLAYER.RXBYTES x8/1000//RX BW_CFG

DL Iub Usage onUser Plane

ATM TransmissionVS.AAL2PATH.PVCLAYER.TXBYTESVS.AAL2PATH.PVCLAYER.RXBYTESIP transmission in non-pooled networking:

VS.IPPATH.IPLAYER.TXBYTESVS.IPPATH.IPLAYER.RXBYTES

IP transmission in resource poolnetworking:

VS.IPPOOL.ANI.IPLAYER.TXBYTESVS.IPPOOL.ANI.IPLAYER.RXBYTES

ATM TransmissionDL Iub Usage on User Plane = Sum

(VS.AAL2PATH.PVCLAYER.TXBYTES)x 8//1000/TX BW_CFG

IP transmission in non-pooled networking:DL Iub Usage on User Plane = Sum

(VS.IPPATH.IPLAYER.TXBYTES) x8//1000/TX BW_CFG

IP transmission in resource pool networking:DL Iub Usage on User Plane =

VS.IPPOOL.ANI.IPLAYER.TXBYTES x8//1000/TX BW_CFG

UL Iub Usage onUser Plane

ATM TransmissionUL Iub Usage on User Plane = Sum

(VS.AAL2PATH.PVCLAYER.RXBYTES)x 8//1000/RX BW_CFG

IP transmission in non-pooled networking:UL Iub Usage on User Plane = Sum

(VS.IPPATH.IPLAYER.RXBYTES) x8//1000/RX BW_CFG

IP transmission in resource pool networking:UL Iub Usage on User Plane =

VS.IPPOOL.ANI.IPLAYER.RXBYTES x8//1000/RX BW_CFG

IP ConnectionSetup Success

Rate

VS.ANI.IP.Conn.Estab.SuccVS.ANI.IP.Conn.Estab.Att

VS.ANI.IP.Conn.Estab.Succ/VS.ANI.IP.Conn.Estab.Att

PCH/FACH Usage-related MetricsPCH Usage VS.UTRAN.AttPaging1 VS.UTRAN.AttPaging1/( x 60 x

5/0.01)FACH Usage VS.CRNCIubBytesFACH.Tx

VS.PCH.Bandwidth.UsageRateVS.SRBNum.FACH

VS.OneSRBTTINum.FACHVS.IndepTRBNum.FACH

(1) Utilization of FACH carried on non-standalone SCCPCH

FACH Usage =VS.CRNCIubBytesFACH.Tx x 8/((60 x

x 168 x 1/0.01) xVS.PCH.Bandwidth.UsageRate x 6/7 + (60

x x 360 x 1/0.01) x (1 -VS.PCH.Bandwidth.UsageRate x 6/7))

where,VS.PCH.Bandwidth.UsageRate =

/( x

x 60)

(2) Utilization of FACH carried onstandalone SCCPCH

FACH Usage = ((VS.SRBNum.FACH -VS.OneSRBTTINum.FACH)/2 +

VS.OneSRBTTINum.FACH +VS.IndepTRBNum.FACH)/( x

60/0.01)RACH Usage VS.CRNCIubBytesRACH.Rx

VS.TRBNum.RACHVS.TRBNum.RACH

RACH Usage =((VS.CRNCIubBytesRACH.Rx -

VS.TRBNum.RACH x 360/8) x 8/168)/( x 60 x 4/0.02) +

VS.TRBNum.RACH/( x 60 x 4/0.02)




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OVSF Usage-related MetricsOVSF Quantity VS.RAB.SFOccupy VS.RAB.SFOccupy

OVSF Usage VS.RAB.SFOccupy.Ratio VS.RAB.SFOccupy/256DCH OVSF

UsageVS.SingleRAB.SF4VS.MultRAB.SF4VS.MultRAB.SF8

VS.SingleRAB.SF8

VS.MultRAB.SF16VS.SingleRAB.SF16VS.SingleRAB.SF32VS.MultRAB.SF32VS.MultRAB.SF64

VS.SingleRAB.SF64VS.SingleRAB.SF128VS.MultRAB.SF128

VS.SingleRAB.SF256VS.MultRAB.SF256

DCH OVSF Usage =DCH_OVSF_CODE/DCH_OVSF_CODE_Ava

whereDCH_OVSF_CODE =

( +) x 64 +( +

) x 32 +( +

) x 16 +( +

) x 8 +( +

) x 4 +( +

) x 2 +( +

)CPU Load-related Metrics

CP/UP CPU

Load

VS.SUBSYS.CPULOAD.MEAN VS.SUBSYS.CPULOAD.MEAN

RMP CPU Load VS.CPU.CPULOAD.MEAN VS.CPU.CPULOAD.MEANINT Load VS.CPU.CPULOAD.MEAN

VS.INT.TRANSLOAD.RATIO.MEANVS.CPU.CPULOAD.MEAN

VS.INT.TRANSLOAD.RATIO.MEANCredit Resource Usage-related Metrics

License-based Downlink CE

Us